Which of the following is the most common adverse effect of metformin?

Correct Answer: C

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: A

Rationale: SERMs (choice A) like tamoxifen act as estrogen agonists (e.g., bone) and antagonists (e.g., breast), a tissue-selective property defining their utility in cancer and osteoporosis. They don't use unique receptors (choice B), combine estrogen/progestin agonism (choice C), or inhibit aromatase (choice D, anastrozole's role). This selectivity is critical for targeted therapy.

Correct Answer: B

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: B

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: A

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.